Feature request: Performance diagrams

[pfetsch]

A suggestion for a feature: Taking several variants (settings) run on the same testset, generate a performance diagram.

This could be the Dolan and Moré performance diagram, but they depend heavily on the best variant. So I would suggest to generate a "number/percentage of instances solved" (y-axis) vs. "time" (x-axis) diagram, i.e., the y-axis displays for every point in time the number/percentage of instances solved up to this time.

The figures could be generated using own code or gnuplot or tikz/pgfplots. The latter option would allow to include the figures into papers in a nice way, but one would need to also store the results in the file.